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Memorandum

TO: R. Q. Anderson/B. Carter/D. S. Senn/D. Sarles/G. F. Demich/R. C. Wade/G. E. Smith/A. McDonald/D. Larson/R. Johnson/
J. C Lenzi/G. Janousek
FROM: M. M. Lwin/C. C. Ruth, 7340
DATE: May 2, 1994
SUBJECT: Use of Approach Slabs for Bridge Ends

There is apparently some question as to whether or not approach slabs are required on all bridge ends. Approach slabs perform an important function because they span across areas that have a high potential for settlement. The design manual indicated that approach slabs are required for all bridges.. The Bridge and Structures Office supports this requirement. Approach slabs should only be deleted if there is assurance that there will be little or no future settlement adjacent to the pavement seat at the bridge ends.

The HQ Materials Lab should be contacted regarding the potential for long-term settlement adjacent to the pavement seat. The final decision to delete approach slabs should have concurrence of the HQ Materials Lab and the district Program Development Engineer. The Bridge and Structures Office will continue our practice of designing all bridges for approach slabs.

CCR

cc:     K. N. Kirker

         Y. A. Mhatre

         R. T. Shaefer

         W. A. Whitney